// Copyright (c) 2011, The TOFT Authors. All rights reserved.
// GLOBAL_NOLINT(whitespace/operators)

#include "toft/base/string/string_piece.h"

#include "thirdparty/gtest/gtest.h"

namespace toft {

char g_s1[] = "http://finance.qq.com/a/20101228/http://finance.qq.com/a/20101228/006335.htm";
char g_s2[] = "http://finance.qq.com/a/20101228/http://finance.qq.com/a/20101228/006336.htm";

TEST(Test, Correction)
{
    StringPiece s1(g_s1, sizeof(g_s1) - 1);
    StringPiece s2(g_s2, sizeof(g_s2) - 1);

    StringPiece sp1(g_s1, sizeof(g_s1) - 1);
    StringPiece sp2(g_s2, sizeof(g_s2) - 1);

    EXPECT_EQ(s1 == s2, sp1 == sp2);
    EXPECT_EQ(s1 != s2, sp1 != sp2);
    EXPECT_EQ(s1 < s2, sp1 < sp2);
    EXPECT_EQ(s1 <= s2, sp1 <= sp2);
    EXPECT_EQ(s1 > s2, sp1 > sp2);
    EXPECT_EQ(s1 >= s2, sp1 >= sp2);
}

TEST(StringPiece, memcmp_Performance)
{
    const char* volatile s1 = g_s1;
    const char* volatile s2 = g_s2;
    int total = 0;
    for (int i = 0; i < 1000000; ++i)
        total += memcmp(s1, s2, sizeof(g_s1) - 1);
    volatile int n = total;
    (void) n;
}

#define TEST_COMPARE_PERFORMANCE(op, name) \
    TEST(StringPiece, name##Performance) \
{ \
    char* volatile s1 = g_s1; \
    char* volatile s2 = g_s2; \
    int total = 0; \
    for (int i = 0; i < 1000000; ++i) {\
        StringPiece sp1(s1, sizeof(g_s1) - 1); \
        StringPiece sp2(s2, sizeof(g_s2) - 1); \
        total += sp1 op sp2; \
        ++s1[0], ++s2[0]; \
    } \
    volatile int n = total; \
    (void) n; \
}

TEST_COMPARE_PERFORMANCE(==, Eq)
TEST_COMPARE_PERFORMANCE(!=, Ne)
TEST_COMPARE_PERFORMANCE(>, Gt)
TEST_COMPARE_PERFORMANCE(>=, Ge)
TEST_COMPARE_PERFORMANCE(<, Lt)
TEST_COMPARE_PERFORMANCE(<=, Le)

TEST(StringPieceTest, CheckComparisonOperators) {
#define CMP_Y(op, x, y)                                               \
        ASSERT_TRUE((StringPiece((x)) op StringPiece((y))));               \
        ASSERT_TRUE((StringPiece((x)).compare(StringPiece((y))) op 0))

#define CMP_N(op, x, y)                                          \
        ASSERT_FALSE(StringPiece((x)) op StringPiece((y)));               \
        ASSERT_FALSE(StringPiece((x)).compare(StringPiece((y))) op 0)

    CMP_Y(==, "",   "");
    CMP_Y(==, "a",  "a");
    CMP_Y(==, "aa", "aa");
    CMP_N(==, "a",  "");
    CMP_N(==, "",   "a");
    CMP_N(==, "a",  "b");
    CMP_N(==, "a",  "aa");
    CMP_N(==, "aa", "a");

    CMP_N(!=, "",   "");
    CMP_N(!=, "a",  "a");
    CMP_N(!=, "aa", "aa");
    CMP_Y(!=, "a",  "");
    CMP_Y(!=, "",   "a");
    CMP_Y(!=, "a",  "b");
    CMP_Y(!=, "a",  "aa");
    CMP_Y(!=, "aa", "a");

    CMP_Y(<, "a",  "b");
    CMP_Y(<, "a",  "aa");
    CMP_Y(<, "aa", "b");
    CMP_Y(<, "aa", "bb");
    CMP_N(<, "a",  "a");
    CMP_N(<, "b",  "a");
    CMP_N(<, "aa", "a");
    CMP_N(<, "b",  "aa");
    CMP_N(<, "bb", "aa");

    CMP_Y(<=, "a",  "a");
    CMP_Y(<=, "a",  "b");
    CMP_Y(<=, "a",  "aa");
    CMP_Y(<=, "aa", "b");
    CMP_Y(<=, "aa", "bb");
    CMP_N(<=, "b",  "a");
    CMP_N(<=, "aa", "a");
    CMP_N(<=, "b",  "aa");
    CMP_N(<=, "bb", "aa");

    CMP_N(>=, "a",  "b");
    CMP_N(>=, "a",  "aa");
    CMP_N(>=, "aa", "b");
    CMP_N(>=, "aa", "bb");
    CMP_Y(>=, "a",  "a");
    CMP_Y(>=, "b",  "a");
    CMP_Y(>=, "aa", "a");
    CMP_Y(>=, "b",  "aa");
    CMP_Y(>=, "bb", "aa");

    CMP_N(>, "a",  "a");
    CMP_N(>, "a",  "b");
    CMP_N(>, "a",  "aa");
    CMP_N(>, "aa", "b");
    CMP_N(>, "aa", "bb");
    CMP_Y(>, "b",  "a");
    CMP_Y(>, "aa", "a");
    CMP_Y(>, "b",  "aa");
    CMP_Y(>, "bb", "aa");

    std::string x;
    for (int i = 0; i < 256; i++) {
        x += 'a';
        std::string y = x;
        CMP_Y(==, x, y);
        for (int j = 0; j < i; j++) {
            std::string z = x;
            z[j] = 'b';       // Differs in position 'j'
            CMP_N(==, x, z);
        }
    }

#undef CMP_Y
#undef CMP_N
}

TEST(StringPieceTest, CheckSTL) {
    StringPiece a("abcdefghijklmnopqrstuvwxyz");
    StringPiece b("abc");
    StringPiece c("xyz");
    StringPiece d("foobar");
    StringPiece e;
    std::string temp("123");
    temp += '\0';
    temp += "456";
    StringPiece f(temp);

    ASSERT_EQ(a[6], 'g');
    ASSERT_EQ(b[0], 'a');
    ASSERT_EQ(c[2], 'z');
    ASSERT_EQ(f[3], '\0');
    ASSERT_EQ(f[5], '5');

    ASSERT_EQ(*d.data(), 'f');
    ASSERT_EQ(d.data()[5], 'r');
    ASSERT_TRUE(e.data() == NULL);

    ASSERT_EQ(*a.begin(), 'a');
    ASSERT_EQ(*(b.begin() + 2), 'c');
    ASSERT_EQ(*(c.end() - 1), 'z');

    ASSERT_EQ(*a.rbegin(), 'z');
    ASSERT_EQ(*(b.rbegin() + 2), 'a');
    ASSERT_EQ(*(c.rend() - 1), 'x');
    ASSERT_TRUE(a.rbegin() + 26 == a.rend());

    ASSERT_EQ(a.size(), 26U);
    ASSERT_EQ(b.size(), 3U);
    ASSERT_EQ(c.size(), 3U);
    ASSERT_EQ(d.size(), 6U);
    ASSERT_EQ(e.size(), 0U);
    ASSERT_EQ(f.size(), 7U);

    ASSERT_TRUE(!d.empty());
    ASSERT_TRUE(d.begin() != d.end());
    ASSERT_TRUE(d.begin() + 6 == d.end());

    ASSERT_TRUE(e.empty());
    ASSERT_TRUE(e.begin() == e.end());

    d.clear();
    ASSERT_EQ(d.size(), 0U);
    ASSERT_TRUE(d.empty());
    ASSERT_TRUE(d.data() == NULL);
    ASSERT_TRUE(d.begin() == d.end());

    ASSERT_GE(a.max_size(), a.capacity());
    ASSERT_GE(a.capacity(), a.size());

    char buf[4] = { '%', '%', '%', '%' };
    ASSERT_EQ(a.copy(buf, 4), 4U);
    ASSERT_EQ(buf[0], a[0]);
    ASSERT_EQ(buf[1], a[1]);
    ASSERT_EQ(buf[2], a[2]);
    ASSERT_EQ(buf[3], a[3]);
    ASSERT_EQ(a.copy(buf, 3, 7), 3U);
    ASSERT_EQ(buf[0], a[7]);
    ASSERT_EQ(buf[1], a[8]);
    ASSERT_EQ(buf[2], a[9]);
    ASSERT_EQ(buf[3], a[3]);
    ASSERT_EQ(c.copy(buf, 99), 3U);
    ASSERT_EQ(buf[0], c[0]);
    ASSERT_EQ(buf[1], c[1]);
    ASSERT_EQ(buf[2], c[2]);
    ASSERT_EQ(buf[3], a[3]);

    ASSERT_EQ(StringPiece::npos, std::string::npos);

    ASSERT_EQ(a.find(b), 0U);
    ASSERT_EQ(a.find(b, 1), StringPiece::npos);
    ASSERT_EQ(a.find(c), 23U);
    ASSERT_EQ(a.find(c, 9), 23U);
    ASSERT_EQ(a.find(c, StringPiece::npos), StringPiece::npos);
    ASSERT_EQ(b.find(c), StringPiece::npos);
    ASSERT_EQ(b.find(c, StringPiece::npos), StringPiece::npos);
    ASSERT_EQ(a.find(d), 0U);
    ASSERT_EQ(a.find(e), 0U);
    ASSERT_EQ(a.find(d, 12), 12U);
    ASSERT_EQ(a.find(e, 17), 17U);
    StringPiece g("xx not found bb");
    ASSERT_EQ(a.find(g), StringPiece::npos);
    // empty string nonsense
    ASSERT_EQ(d.find(b), StringPiece::npos);
    ASSERT_EQ(e.find(b), StringPiece::npos);
    ASSERT_EQ(d.find(b, 4), StringPiece::npos);
    ASSERT_EQ(e.find(b, 7), StringPiece::npos);

    size_t empty_search_pos = std::string().find(std::string());
    ASSERT_EQ(d.find(d), empty_search_pos);
    ASSERT_EQ(d.find(e), empty_search_pos);
    ASSERT_EQ(e.find(d), empty_search_pos);
    ASSERT_EQ(e.find(e), empty_search_pos);
    ASSERT_EQ(d.find(d, 4), std::string().find(std::string(), 4));
    ASSERT_EQ(d.find(e, 4), std::string().find(std::string(), 4));
    ASSERT_EQ(e.find(d, 4), std::string().find(std::string(), 4));
    ASSERT_EQ(e.find(e, 4), std::string().find(std::string(), 4));

    ASSERT_EQ(a.find('a'), 0U);
    ASSERT_EQ(a.find('c'), 2U);
    ASSERT_EQ(a.find('z'), 25U);
    ASSERT_EQ(a.find('$'), StringPiece::npos);
    ASSERT_EQ(a.find('\0'), StringPiece::npos);
    ASSERT_EQ(f.find('\0'), 3U);
    ASSERT_EQ(f.find('3'), 2U);
    ASSERT_EQ(f.find('5'), 5U);
    ASSERT_EQ(g.find('o'), 4U);
    ASSERT_EQ(g.find('o', 4), 4U);
    ASSERT_EQ(g.find('o', 5), 8U);
    ASSERT_EQ(a.find('b', 5), StringPiece::npos);
    // empty string nonsense
    ASSERT_EQ(d.find('\0'), StringPiece::npos);
    ASSERT_EQ(e.find('\0'), StringPiece::npos);
    ASSERT_EQ(d.find('\0', 4), StringPiece::npos);
    ASSERT_EQ(e.find('\0', 7), StringPiece::npos);
    ASSERT_EQ(d.find('x'), StringPiece::npos);
    ASSERT_EQ(e.find('x'), StringPiece::npos);
    ASSERT_EQ(d.find('x', 4), StringPiece::npos);
    ASSERT_EQ(e.find('x', 7), StringPiece::npos);

    ASSERT_EQ(a.rfind(b), 0U);
    ASSERT_EQ(a.rfind(b, 1), 0U);
    ASSERT_EQ(a.rfind(c), 23U);
    ASSERT_EQ(a.rfind(c, 22U), StringPiece::npos);
    ASSERT_EQ(a.rfind(c, 1U), StringPiece::npos);
    ASSERT_EQ(a.rfind(c, 0U), StringPiece::npos);
    ASSERT_EQ(b.rfind(c), StringPiece::npos);
    ASSERT_EQ(b.rfind(c, 0U), StringPiece::npos);
    ASSERT_EQ(a.rfind(d), (size_t) a.as_string().rfind(std::string()));
    ASSERT_EQ(a.rfind(e), a.as_string().rfind(std::string()));
    ASSERT_EQ(a.rfind(d, 12), 12U);
    ASSERT_EQ(a.rfind(e, 17), 17U);
    ASSERT_EQ(a.rfind(g), StringPiece::npos);
    ASSERT_EQ(d.rfind(b), StringPiece::npos);
    ASSERT_EQ(e.rfind(b), StringPiece::npos);
    ASSERT_EQ(d.rfind(b, 4), StringPiece::npos);
    ASSERT_EQ(e.rfind(b, 7), StringPiece::npos);
    // empty string nonsense
    ASSERT_EQ(d.rfind(d, 4), std::string().rfind(std::string()));
    ASSERT_EQ(e.rfind(d, 7), std::string().rfind(std::string()));
    ASSERT_EQ(d.rfind(e, 4), std::string().rfind(std::string()));
    ASSERT_EQ(e.rfind(e, 7), std::string().rfind(std::string()));
    ASSERT_EQ(d.rfind(d), std::string().rfind(std::string()));
    ASSERT_EQ(e.rfind(d), std::string().rfind(std::string()));
    ASSERT_EQ(d.rfind(e), std::string().rfind(std::string()));
    ASSERT_EQ(e.rfind(e), std::string().rfind(std::string()));

    ASSERT_EQ(g.rfind('o'), 8U);
    ASSERT_EQ(g.rfind('q'), StringPiece::npos);
    ASSERT_EQ(g.rfind('o', 8), 8U);
    ASSERT_EQ(g.rfind('o', 7), 4U);
    ASSERT_EQ(g.rfind('o', 3), StringPiece::npos);
    ASSERT_EQ(f.rfind('\0'), 3U);
    ASSERT_EQ(f.rfind('\0', 12), 3U);
    ASSERT_EQ(f.rfind('3'), 2U);
    ASSERT_EQ(f.rfind('5'), 5U);
    // empty string nonsense
    ASSERT_EQ(d.rfind('o'), StringPiece::npos);
    ASSERT_EQ(e.rfind('o'), StringPiece::npos);
    ASSERT_EQ(d.rfind('o', 4), StringPiece::npos);
    ASSERT_EQ(e.rfind('o', 7), StringPiece::npos);

    ASSERT_EQ(a.find_first_of(b), 0U);
    ASSERT_EQ(a.find_first_of(b, 0), 0U);
    ASSERT_EQ(a.find_first_of(b, 1), 1U);
    ASSERT_EQ(a.find_first_of(b, 2), 2U);
    ASSERT_EQ(a.find_first_of(b, 3), StringPiece::npos);
    ASSERT_EQ(a.find_first_of(c), 23U);
    ASSERT_EQ(a.find_first_of(c, 23), 23U);
    ASSERT_EQ(a.find_first_of(c, 24), 24U);
    ASSERT_EQ(a.find_first_of(c, 25), 25U);
    ASSERT_EQ(a.find_first_of(c, 26), StringPiece::npos);
    ASSERT_EQ(g.find_first_of(b), 13U);
    ASSERT_EQ(g.find_first_of(c), 0U);
    ASSERT_EQ(a.find_first_of(f), StringPiece::npos);
    ASSERT_EQ(f.find_first_of(a), StringPiece::npos);
    // empty string nonsense
    ASSERT_EQ(a.find_first_of(d), StringPiece::npos);
    ASSERT_EQ(a.find_first_of(e), StringPiece::npos);
    ASSERT_EQ(d.find_first_of(b), StringPiece::npos);
    ASSERT_EQ(e.find_first_of(b), StringPiece::npos);
    ASSERT_EQ(d.find_first_of(d), StringPiece::npos);
    ASSERT_EQ(e.find_first_of(d), StringPiece::npos);
    ASSERT_EQ(d.find_first_of(e), StringPiece::npos);
    ASSERT_EQ(e.find_first_of(e), StringPiece::npos);

    ASSERT_EQ(a.find_first_not_of(b), 3U);
    ASSERT_EQ(a.find_first_not_of(c), 0U);
    ASSERT_EQ(b.find_first_not_of(a), StringPiece::npos);
    ASSERT_EQ(c.find_first_not_of(a), StringPiece::npos);
    ASSERT_EQ(f.find_first_not_of(a), 0U);
    ASSERT_EQ(a.find_first_not_of(f), 0U);
    ASSERT_EQ(a.find_first_not_of(d), 0U);
    ASSERT_EQ(a.find_first_not_of(e), 0U);
    // empty string nonsense
    ASSERT_EQ(d.find_first_not_of(a), StringPiece::npos);
    ASSERT_EQ(e.find_first_not_of(a), StringPiece::npos);
    ASSERT_EQ(d.find_first_not_of(d), StringPiece::npos);
    ASSERT_EQ(e.find_first_not_of(d), StringPiece::npos);
    ASSERT_EQ(d.find_first_not_of(e), StringPiece::npos);
    ASSERT_EQ(e.find_first_not_of(e), StringPiece::npos);

    StringPiece h("====");
    ASSERT_EQ(h.find_first_not_of('='), StringPiece::npos);
    ASSERT_EQ(h.find_first_not_of('=', 3), StringPiece::npos);
    ASSERT_EQ(h.find_first_not_of('\0'), 0U);
    ASSERT_EQ(g.find_first_not_of('x'), 2U);
    ASSERT_EQ(f.find_first_not_of('\0'), 0U);
    ASSERT_EQ(f.find_first_not_of('\0', 3), 4U);
    ASSERT_EQ(f.find_first_not_of('\0', 2), 2U);
    // empty string nonsense
    ASSERT_EQ(d.find_first_not_of('x'), StringPiece::npos);
    ASSERT_EQ(e.find_first_not_of('x'), StringPiece::npos);
    ASSERT_EQ(d.find_first_not_of('\0'), StringPiece::npos);
    ASSERT_EQ(e.find_first_not_of('\0'), StringPiece::npos);

    //  StringPiece g("xx not found bb");
    StringPiece i("56");
    ASSERT_EQ(h.find_last_of(a), StringPiece::npos);
    ASSERT_EQ(g.find_last_of(a), g.size() - 1);
    ASSERT_EQ(a.find_last_of(b), 2U);
    ASSERT_EQ(a.find_last_of(c), a.size() - 1);
    ASSERT_EQ(f.find_last_of(i), 6U);
    ASSERT_EQ(a.find_last_of('a'), 0U);
    ASSERT_EQ(a.find_last_of('b'), 1U);
    ASSERT_EQ(a.find_last_of('z'), 25U);
    ASSERT_EQ(a.find_last_of('a', 5), 0U);
    ASSERT_EQ(a.find_last_of('b', 5), 1U);
    ASSERT_EQ(a.find_last_of('b', 0), StringPiece::npos);
    ASSERT_EQ(a.find_last_of('z', 25), 25U);
    ASSERT_EQ(a.find_last_of('z', 24), StringPiece::npos);
    ASSERT_EQ(f.find_last_of(i, 5), 5U);
    ASSERT_EQ(f.find_last_of(i, 6), 6U);
    ASSERT_EQ(f.find_last_of(a, 4), StringPiece::npos);
    // empty string nonsense
    ASSERT_EQ(f.find_last_of(d), StringPiece::npos);
    ASSERT_EQ(f.find_last_of(e), StringPiece::npos);
    ASSERT_EQ(f.find_last_of(d, 4), StringPiece::npos);
    ASSERT_EQ(f.find_last_of(e, 4), StringPiece::npos);
    ASSERT_EQ(d.find_last_of(d), StringPiece::npos);
    ASSERT_EQ(d.find_last_of(e), StringPiece::npos);
    ASSERT_EQ(e.find_last_of(d), StringPiece::npos);
    ASSERT_EQ(e.find_last_of(e), StringPiece::npos);
    ASSERT_EQ(d.find_last_of(f), StringPiece::npos);
    ASSERT_EQ(e.find_last_of(f), StringPiece::npos);
    ASSERT_EQ(d.find_last_of(d, 4), StringPiece::npos);
    ASSERT_EQ(d.find_last_of(e, 4), StringPiece::npos);
    ASSERT_EQ(e.find_last_of(d, 4), StringPiece::npos);
    ASSERT_EQ(e.find_last_of(e, 4), StringPiece::npos);
    ASSERT_EQ(d.find_last_of(f, 4), StringPiece::npos);
    ASSERT_EQ(e.find_last_of(f, 4), StringPiece::npos);

    ASSERT_EQ(a.find_last_not_of(b), a.size() - 1);
    ASSERT_EQ(a.find_last_not_of(c), 22U);
    ASSERT_EQ(b.find_last_not_of(a), StringPiece::npos);
    ASSERT_EQ(b.find_last_not_of(b), StringPiece::npos);
    ASSERT_EQ(f.find_last_not_of(i), 4U);
    ASSERT_EQ(a.find_last_not_of(c, 24), 22U);
    ASSERT_EQ(a.find_last_not_of(b, 3), 3U);
    ASSERT_EQ(a.find_last_not_of(b, 2), StringPiece::npos);
    // empty string nonsense
    ASSERT_EQ(f.find_last_not_of(d), f.size() - 1);
    ASSERT_EQ(f.find_last_not_of(e), f.size() - 1);
    ASSERT_EQ(f.find_last_not_of(d, 4), 4U);
    ASSERT_EQ(f.find_last_not_of(e, 4), 4U);
    ASSERT_EQ(d.find_last_not_of(d), StringPiece::npos);
    ASSERT_EQ(d.find_last_not_of(e), StringPiece::npos);
    ASSERT_EQ(e.find_last_not_of(d), StringPiece::npos);
    ASSERT_EQ(e.find_last_not_of(e), StringPiece::npos);
    ASSERT_EQ(d.find_last_not_of(f), StringPiece::npos);
    ASSERT_EQ(e.find_last_not_of(f), StringPiece::npos);
    ASSERT_EQ(d.find_last_not_of(d, 4), StringPiece::npos);
    ASSERT_EQ(d.find_last_not_of(e, 4), StringPiece::npos);
    ASSERT_EQ(e.find_last_not_of(d, 4), StringPiece::npos);
    ASSERT_EQ(e.find_last_not_of(e, 4), StringPiece::npos);
    ASSERT_EQ(d.find_last_not_of(f, 4), StringPiece::npos);
    ASSERT_EQ(e.find_last_not_of(f, 4), StringPiece::npos);

    ASSERT_EQ(h.find_last_not_of('x'), h.size() - 1);
    ASSERT_EQ(h.find_last_not_of('='), StringPiece::npos);
    ASSERT_EQ(b.find_last_not_of('c'), 1U);
    ASSERT_EQ(h.find_last_not_of('x', 2), 2U);
    ASSERT_EQ(h.find_last_not_of('=', 2), StringPiece::npos);
    ASSERT_EQ(b.find_last_not_of('b', 1), 0U);
    // empty string nonsense
    ASSERT_EQ(d.find_last_not_of('x'), StringPiece::npos);
    ASSERT_EQ(e.find_last_not_of('x'), StringPiece::npos);
    ASSERT_EQ(d.find_last_not_of('\0'), StringPiece::npos);
    ASSERT_EQ(e.find_last_not_of('\0'), StringPiece::npos);

    ASSERT_EQ(a.substr(0, 3), b);
    ASSERT_EQ(a.substr(23), c);
    ASSERT_EQ(a.substr(23, 3), c);
    ASSERT_EQ(a.substr(23, 99), c);
    ASSERT_EQ(a.substr(0), a);
    ASSERT_EQ(a.substr(3, 2), "de");
    // empty string nonsense
    ASSERT_EQ(a.substr(99, 2), e);
    ASSERT_EQ(d.substr(99), e);
    ASSERT_EQ(d.substr(0, 99), e);
    ASSERT_EQ(d.substr(99, 99), e);
}

TEST(StringPieceTest, CheckCustom) {
    StringPiece a("foobar");
    std::string s1("123");
    s1 += '\0';
    s1 += "456";
    StringPiece b(s1);
    StringPiece e;
    std::string s2;

    // copy_to_string
    a.copy_to_string(&s2);
    ASSERT_EQ(s2.size(), 6U);
    ASSERT_EQ(s2, "foobar");
    b.copy_to_string(&s2);
    ASSERT_EQ(s2.size(), 7U);
    ASSERT_EQ(s1, s2);
    e.copy_to_string(&s2);
    ASSERT_TRUE(s2.empty());

    // append_to_string
    s2.erase();
    a.append_to_string(&s2);
    ASSERT_EQ(s2.size(), 6U);
    ASSERT_EQ(s2, "foobar");
    a.append_to_string(&s2);
    ASSERT_EQ(s2.size(), 12U);
    ASSERT_EQ(s2, "foobarfoobar");

    // starts_with
    ASSERT_TRUE(a.starts_with(a));
    ASSERT_TRUE(a.starts_with("foo"));
    ASSERT_TRUE(a.starts_with(e));
    ASSERT_TRUE(b.starts_with(s1));
    ASSERT_TRUE(b.starts_with(b));
    ASSERT_TRUE(b.starts_with(e));
    ASSERT_TRUE(e.starts_with(""));
    ASSERT_TRUE(!a.starts_with(b));
    ASSERT_TRUE(!b.starts_with(a));
    ASSERT_TRUE(!e.starts_with(a));

    // ends with
    ASSERT_TRUE(a.ends_with(a));
    ASSERT_TRUE(a.ends_with("bar"));
    ASSERT_TRUE(a.ends_with(e));
    ASSERT_TRUE(b.ends_with(s1));
    ASSERT_TRUE(b.ends_with(b));
    ASSERT_TRUE(b.ends_with(e));
    ASSERT_TRUE(e.ends_with(""));
    ASSERT_TRUE(!a.ends_with(b));
    ASSERT_TRUE(!b.ends_with(a));
    ASSERT_TRUE(!e.ends_with(a));

    // remove_prefix
    StringPiece c(a);
    c.remove_prefix(3);
    ASSERT_EQ(c, "bar");
    c = a;
    c.remove_prefix(0);
    ASSERT_EQ(c, a);
    c.remove_prefix(c.size());
    ASSERT_EQ(c, e);

    // remove_suffix
    c = a;
    c.remove_suffix(3);
    ASSERT_EQ(c, "foo");
    c = a;
    c.remove_suffix(0);
    ASSERT_EQ(c, a);
    c.remove_suffix(c.size());
    ASSERT_EQ(c, e);

    // set
    c.set("foobar", 6);
    ASSERT_EQ(c, a);
    c.set("foobar", 0);
    ASSERT_EQ(c, e);
    c.set("foobar", 7);
    ASSERT_NE(c, a);

    c.set("foobar");
    ASSERT_EQ(c, a);

    c.set(static_cast<const void*>("foobar"), 6);
    ASSERT_EQ(c, a);
    c.set(static_cast<const void*>("foobar"), 0);
    ASSERT_EQ(c, e);
    c.set(static_cast<const void*>("foobar"), 7);
    ASSERT_NE(c, a);

    // as_string
    std::string s3(a.as_string().c_str(), 7);
    ASSERT_EQ(c, s3);
    std::string s4(e.as_string());
    ASSERT_TRUE(s4.empty());
}

TEST(StringPieceTest, CheckNULL) {
    // we used to crash here, but now we don't.
    StringPiece s;
    ASSERT_EQ(s.data(), (const char*)NULL);
    ASSERT_EQ(s.size(), 0U);

    s.set(NULL);
    ASSERT_EQ(s.data(), (const char*)NULL);
    ASSERT_EQ(s.size(), 0U);
}

TEST(StringPieceTest, CheckComparisons2) {
    StringPiece abc("abcdefghijklmnopqrstuvwxyz");

    // check comparison operations on strings longer than 4 bytes.
//    ASSERT_TRUE(abc == StringPiece("abcdefghijklmnopqrstuvwxyz"));
//    ASSERT_TRUE(abc.compare(StringPiece("abcdefghijklmnopqrstuvwxyz")) == 0);

//    ASSERT_TRUE(abc < StringPiece("abcdefghijklmnopqrstuvwxzz"));
//    ASSERT_TRUE(abc.compare(StringPiece("abcdefghijklmnopqrstuvwxzz")) < 0);

//    ASSERT_TRUE(abc > StringPiece("abcdefghijklmnopqrstuvwxyy"));
//    ASSERT_TRUE(abc.compare(StringPiece("abcdefghijklmnopqrstuvwxyy")) > 0);

    // starts_with
//    ASSERT_TRUE(abc.starts_with(abc));
//    ASSERT_TRUE(abc.starts_with("abcdefghijklm"));
//    ASSERT_TRUE(!abc.starts_with("abcdefguvwxyz"));

    // ends_with
//    ASSERT_TRUE(abc.ends_with(abc));
//    ASSERT_TRUE(!abc.ends_with("abcdefguvwxyz"));
    ASSERT_TRUE(abc.ends_with("nopqrstuvwxyz"));
}

TEST(StringPieceTest, StringCompareNotAmbiguous) {
    ASSERT_EQ("hello", std::string("hello"));
    ASSERT_LT("hello", std::string("world"));
}

TEST(StringPieceTest, HeterogenousStringPieceEquals) {
    static const char kHello[] = "hellohellohellohellohellohellohello";
    ASSERT_TRUE(StringPiece(kHello) == std::string(kHello));
    ASSERT_TRUE(kHello == StringPiece(kHello));
}

TEST(StringPieceTest, IgnoreCaseCompare)
{
    StringPiece sp("hello");
    ASSERT_EQ(0, sp.ignore_case_compare("HELLO"));
    ASSERT_LT(sp.ignore_case_compare("iELLO"), 0);
    ASSERT_GT(sp.ignore_case_compare("gELLO"), 0);
    ASSERT_TRUE(sp.ignore_case_equal("HELLO"));
}

TEST(StringPieceTest, FromArray)
{
    static const char hello[10] = "hello";
    StringPiece sp = StringPiece::FromArray(hello);
    EXPECT_EQ(sizeof(hello), sp.size());

    static const unsigned char world[12] = "world";
    sp = StringPiece::FromArray(world);
    EXPECT_EQ(sizeof(world), sp.size());
}

} // namespace toft
